The invention pertains to a tool holder, which retains a cutting insert for engaging a workpiece in a material removal operation, wherein the tool holder provides for internal coolant delivery to the cutting insert during a material removal operation. More specifically, the invention pertains to such a tool holder wherein the structure of the coolant passage in the tool holder improves efficiency of coolant delivery to the cutting insert during a material removal operation. In this regard, the structure of the coolant passage provides for coolant flow in a tangential direction so that flowing coolant does not abruptly impinge a surface so the coolant flow is essentially uninterrupted.
Heretofore, the delivery of coolant to a cutting insert during the material removal operation has been used to improve the overall removal operation. Exemplary patents that disclose various ways to deliver coolant to the cutting insert during the material removal operation are identified as follows: U.S. Pat. No. 4,955,264 to Armbrust, U.S. Pat. No. 5,148,728 to Mazurkiewicz, U.S. Pat. No. 5,340,242 to Armbrust et al., U.S. Pat. No. 6,471,448 to Lagerberg, U.S. Pat. No. 5,388,487 to Danielson, U.S. Pat. No. 8,256,999 to Prichard et al., and U.S. Pat. No. 6,443,672 to Lagerberg.
While existing ways to deliver coolant to the cutting insert, and especially to deliver coolant to the vicinity of the interface between the cutting insert and the workpiece, have performed in a satisfactory manner, there remains the need to improve the efficiency of the delivery of coolant. One drawback of earlier ways to deliver coolant to the interface between the cutting insert and the workpiece during the material removal operation is the occurrence of the flowing coolant abruptly impinging a surface so as to interrupt the coolant flow. This abrupt impingement could cause turbulence and decrease the efficiency of the coolant delivery to the cutting insert. This can be the case especially when under high pressure (e.g., a pressure equal to about 70 bar). Therefore, it would be highly desirable to provide a tool holder, which retains a cutting insert for engaging a workpiece in a material removal operation, wherein the tool holder provides for internal coolant delivery in such a fashion that the flowing coolant does not abruptly impinge the surface defining the coolant chamber. It would highly desirable to provide a tool holder, which retains a cutting insert for engaging a workpiece in a material removal operation, wherein the tool holder provides for internal coolant delivery in such a fashion that increases the efficiency of the delivery of the flowing coolant to the cutting insert.